The present invention relates generally to helmets worn by riders and passengers of bicycles, motorcycles, motorbikes and other vehicles and more particularly motorcycle helmets which by their use suffer from high wind noises.
The wind rushing by and against helmets and particularly those worn by motorcycle riders when traveling at fast speeds subjects the user to loud wind noises due to turbulence, laminar flow and so forth as the helmet passes through the air. These wind noises are not only annoying but under extreme conditions can actually injure the user's ears. Noise levels experienced at the ear of motorcyclists wearing prior art helmets vary depending on the helmet worn, whether or not it has a face shield, the motorcycle speed, the motorcycle brand, the helmet brand, and the amount of traffic. Noise levels of 100 decibels (or even 118 decibels) or more, even with some of the quieter helmets, at higher motorcycle speeds are not unusual. Noise levels higher than 85 decibels for long periods are potentially damaging to the ears. These noise levels exceed levels which allow speech communication or hearing of warning sounds. The noises are often so loud as to drown out or make difficult to hear sounds useful to the driver, such as honking and other sounds of nearby traffic, emergency vehicle sirens, people yelling out dangerous or upcoming traffic conditions, and conversations of adjacent riders.
Attempts in the past to remedy these problems have been only partially successful. For example, U.S. Pat. No. 4,370,758 shows a helmet having devices attached to the sides of the helmet to attenuate noise generated from turbulence as the helmet passes through the air. And U.S. Pat. No. 5,361,419 discloses breakaway air and sound ducts on the side of a helmet. (These two patents are hereby incorporated by reference in their entireties.)